1. Field Of The Invention
The present invention relates to fluid compressors of the pitot type.
2. Description Of The Prior Art
The pitot type pump for pumping liquids is well known. Such a pump is disclosed in U.S. Pat. No. 4,045,145 issued to J. W. Erickson and V. Budrys. A stationary pitot tube is mounted inside a rotating casing or housing. Fluid is delivered to the interior of the housing through a plurality of radial ducts in the walls of the casing which discharge the fluid by centrifugal force. The stationary pitot tube collects the fluid which is rotating with the casing and the ram effect forces the fluid out through the pitot tube.
The pitot type pump can also be utilized as a gas compressor. However, such an apparatus must be operated at much higher speeds than a pitot type pump of the same size and pressurizing capacity, since a fluid such as a gas is much lower in density and compressibility than liquids. A pitot compressor with a liquid separator is disclosed in U.S. Pat. No. 4,059,364 issued to P. H. Anderson and J. W. Erickson.
The high speeds at which a pitot type compressor must operate creates a stress problem in the rotating casing. The prior art casings are constructed as an annular, cup-shaped housing mounted coaxially on a driven shaft and a cover is bolted over the open end of the housing. For the purposes of stress calculations, the casing can be thought of as two, spaced apart discs mounted on the shaft and closed at the periphery by a ring which basically is a free ring. In a typical gas well application, a pitot type compressor would require four or five stages which is impractical